ExxonMobil issues best practice tips on switching fuels in Emission Control Areas

ExxonMobil is advising marine operators to consider the following five key fuel switching tips when entering and exiting Emission Control Areas (ECAs):

• Have a clear switchover procedure – The crew should be familiar with the procedure and testing should be carried out prior to entering crowded and restricted channels to reduce the risk of grounding or collision.
• Outline the best time to switchover – The optimal switchover period differs across vessels. Sufficient time must be given for the fuel system to be flushed of all non-compliant fuel before arriving at an ECA boundary.
• Avoid hazards: know the correct temperature and viscosity – The viscosity of heavy fuel oil (HFO), ECA fuels and marine gas oil (MGO) are very different. The appropriate temperature must be achieved to ensure that the optimum viscosity at the injectors is reached.
• Understand compatibility –There is a risk of fuel incapability when fuels mix during the switching process. This can lead to a possible engine shut down. An on-board industry spot test or a more thorough compatibility test should be conducted to determine fuel compatibility.
• Choose the correct lubricant – A lower base number lubricant should be used when burning low-sulphur fuels. This will allow for the reduced acidic sulphur level in the fuel to be safely neutralised by a lower, more suitable level of alkalinity.